import java.util.Scanner;
public class shanchu {
    public static void main(String[] args) {
        Scanner in=new Scanner(System.in);
        String []a={"aa","bb","cc","ff"};
        System.out.println("请输入一个字符：");
        String i=in.next();
        for(int k=0;k<a.length;k++)
        {
            if(i.equals(a[k]))
            {
                for(int y=k;y<a.length-1;y++)
                {
                    a[y]=a[y+1];
                }
                a[a.length-1]=null;
            }
            System.out.println(a[k]);
        }
    }
}
